Lubricant containing phosphosulfurized hydrocarbon derivative



United States Patent E 6 Claims. (Cl. 252-465) Lubricants having as manysided properties as possible are of constantly increasing significance in view of plant simplication and rationalisation. If a lubricant can simultaneously fulfill several lubricating functions, it is to be preferred, from the operational point of view, to the use of several lubricants of specific effect. Consequently, substituting one polyfunctional product for several lubricants constitutes a step forward in the art.

Lubricants having polyfunctional properties that can find a wide field of application are e.g. those which can simultaneously be used in engines, gears, and hydraulic systems. The specific properties required for these fields of use are in part widely diiferent. A lubricant that is capable of satisfying the various demands has to be adjusted very closely to the various functions it has to fulfill. Below is a list of the various properties of a lubricant (apart from mere lubrication) that are significant for the various fields of use.

Field of application Properties demanded ance. (d) Heat resistance. (e) Dispersing ability. (1') Age resistance. Corrosion resistance. (h) In certain cases also extreme pressure properties.

As is shown in the list, there in the properties.

Thin motor oils, e.g. can be employed in highly loaded gears under certain conditions and mostly not at all. In hydraulic systems they may occasionally be used, but in critical cases their properties do not sufiice.

On the other hand the use of gear oils or typical hydraulic oils is out of the question for engine purposes due to their lack of detergent and neutralizing effect.

Thus any lubricant equally well suited for the application fields A, B, and C has to contain an additive or additive combination which is capable of fulfilling the demands involved.

It has now been found that a lubricant additive that greatly satisfies those demands is obtained by reacting polybutenes that have been treated with phosphorous (V) sulfide with a long-chained monohydric alcohol, preferably an unsaturated alcohol, for example, oleyl alcohol, and if desired reacting the resulting reaction product further with a polyamine. The term polybutenes covers all the polymers of butenes, also of isobutylene.

The use of P S -treated polybutenes in conjunction with alkaline earth hydroxides or in combination with alkaline earth phenolates as lubricant additives has been described in numerous patents.

are in part great difierences 3,321,40t Patented May 23, 1961 ICC However, because of excessive corrosion it is impos sible to use that product by itself although it is dispersing and extreme pressure efl ective. But in the reaction 01 P s -treated polybutenes (molecular weight 500 to 2000) with alcohols, products are obtained which in comparison with the starting material show improvements regarding the following properties:

(1) Corrosion behavior (2) Acidity (greatly reduced) (3) Dispersing ability (4) Heat resistance In addition, a minor improvement in viscosity-temperature behavior is achieved in the oils to which these products are added.

It was found that the most favour-able alcohol for the reaction of the P S -treated polybutene is oleyl alcohol. Tests have shown that this alcohol is preferable to the saturated higher alcohols.

If this reaction product is reacted in a second process step with an amine (polyamine), further improvements in the corrosion behavior, acidity and dispersing ability are obtained, whereas heat resistance and extreme pressure behavior are not negatively aifected. The corrosion behavior is even improved thereby to such a degree that the product can indeed be considered a corrosion protection. The polyamine employed was dipropylene triamine, however, tetra-ethylene pentamine can also be used.

The lubricant of the invention for engines, gears, hydraulic-mechanic or hydraulic systems on a lubricating oil base is characterized by containing, in proportions of from 1 to 20, preferably from 3 to 5 wt. percent, (a) the product of a reaction of a polybutene treated with phosphorous (V) sulfide and having a molecular weight of 500 to 2000 reacted with a monohydric alcohol, preferably having from 12 to 22 carbon atoms per molecular or (b) reaction product of (a) reacted with a polyamine.

The lubricating oils employed are preferably mineral lubricating oils, particularly paraflin base solvent ralfinates.

In addition, the lubricants of the invention can contain, as lubricant additives known per se, metal sulfonates, metal alkyl phenolates, metal alkyl salicylates, metal salts of reaction products of phosphorous (V) sufide and polybutene or metal amino alkyl phenolates as ash containing detergents in concentrations of from 0.5 to 20.0 Wt. percent, metal dialkyl dithiophosphates in concentrations of from 0.1 to 3 Wt. percent, extreme pressure additives on the basis of sulfur, chlorine and/or phosphorous in concentrations of from 0.5 to 10 wt. percent, metal deactivators in concentrations of from 0.01 to 1 wt. percent, and/or alkyl succinic acid imides, copolymers of methacrylic acid and amines, or copolymers of vinyl acetate, fumaric acid esters and maleic acid as dispersers in proportions of from 0.5 to 5 wt. percent.

The preparation of the lubricating oil additives to be employed according to the invention, can be carried out as follows:

A polybutene reacted with phosphorus (V) sulfide (molecular weight 500 to 2000) having a phosphorus content of from 2 to 8 wt. percent and a sulfur content of from 4 to 16 wt. percent is reacted for 1 hour at to 200 C. with from 15 to 50 wt. percent, preferably 25 wt. percent, based on the phosphosulfurized polybutene of, a monovalent, high molecular weight, preferably unsaturated fatty alcohol.

The resulting reaction product can if desired be reacted in a second process step for half an hour at 80 to C. with from 1 to 20 wt. percent polyamine (based on the reaction product obtained in the first step).

3 Example 1 A lubricating oil additive according to the invention is 'epared as follows:

75 g. of a reaction product of P 5 and polybutene iverage molecular weight about 700, phosphorus content 85 wt. percent, sulfur content 6.4 wt. percent) are stirred )r 1 hour at 175 C. with g. technical oleyl alcohol. 1 the reaction hydrogen sulfide escapes and the alcohol )ncentration recedes, which is noted from a reduction f the OH-concentration in the ultrared spectrum. After hour the reaction is finished, which is seen from the amplete disappearance of the OH-group in the ultrared pectrum.

When the product has been cooled to 130 C., 3 wt. ercent dipropylene triamine is added and the mixture tirred for minutes. The conclusion of the reaction is pparent from the complete disappearance of the NHgroup in the ultrared spectrum. The reaction is about 00%.

The reaction product is a dark red viscous liquid that 9 equires no further purification. It is miscible with minral oils as well as with aliphatic, aromatic and naphhenic hydrocarbons in any proportion.

A corrosion test is conducted as follows:

Batches of 95 wt. percent each of a mineral lubricating )il (viscosity about 50 cs. at 50 C.) are mixed with 3 wvt. percent of each of the fOllOWiIlg additives:

(l) polybutene treated with phosphorus (V) sulfide (molecular weight 700),

(2) reaction product of (l) with oleyl alcohol,

(3) reaction product of (2) with dipropylene triamine.

Each bath of 98 ml. of the oil mixed with the respective additive is stirred with 2 ml. water. A copper strip and a bearing segment (ball bearing basin) are placed in each of the mixtures and left therein for 48 hours at 100 C. The results are as follows:

Findings Oil mixture Steel Copper Very greatly corroded Light rust- Moderate sulfide coating. No rust Dark brown discolouring.

Also when higher concentrations are employed, the additives according to the invention supply satisfactory results in this respect.

Example 2 Total piston performance Lubricating oil: (100 max.) Lubricating oil according to invention 88 Comparison oil 89 The comparison shows that the cleansing effect in the engine is definitely favourable for an ash-free product.

Example 3 In combination with ash-containing detergents the above described additive according to the invention, in a 50-hour test in a 4-cylinder diesel engine, shows results similar to those of the conventional ash-free dispersing agents, which, however, contrary to the inventive additive, have a dispersant effect only and no other effect to improve the lubricating oil. The results of these tests are as follows:

Composition Piston performance =max.)

Mineral lubricating oil SAE 20+6% ash-containing detergent+l.3% commercial ash-free dispersant 96 Mineral lubricating oil SAE 20+6% ash-containing detergent+2% additive according to inventrorn- 94.5

Example 4 Mixture Findings after 14 days a) Gasoline and black Immediate sedimentation. (b) (a)+1 g. Piss-treated poly- Complete sedimentatlon.

(c) (a)+1 g. additive according Slight sedimentation major proinvention. portion dispersed.

(d) (a.)+1 g. dispersing agent on The same.

polymethucrylate amino base.

(e) (a) +1 g. copolymer of vinyl acetate, iumaric acid ester and maleic acid.

Slightly increased sedimentation, but still suificient proportion of dispersed black.

Even when it was left standing for several months, the additive according to the invention still showed excellent dispersant capacity, thus ensuring flawless sludge-dispersing behaviour in the engine.

Example 5 Device Result Four Ball Tester-.. Wear 0.33 m. (unalloyed oil 0.6 111111.). Wear data 260 KG (unalloyed oil 140 kg.). FZG Test No switch-over to high wear level, minor chamies)1n the 12 load steps (comparable to hypoid 01 s Rear axle High wear in 9th step (54.5 kg). Normal behaviour up to 9th load stop (one step lower than typical hypoid oils).

The above values show that the extreme pressure properties of these oils almost correspond to those of a hypoid gear oil that satisfies the highest demands. This is of special significance because the conventional dispersants and detergents are known to have no extreme pressure properties.

Example 6 The behaviour towards sealing material is determined by tests in which a simmering-material of L. Freudenberg, Weinheim, is kept in contact with the oil base and the oil base containing the inventive additive for 100 hours at C. The results are as follows:

These values are extraordinarily favourable, since effective extreme pressure additives are known to cause hardening up to 5 Shore units.

Example 7 Also the heat resistance of the additive according to the invention as well as of the lubricating oils prepared therewith is very high. This is shown by the following test results:

Lubricating oil additive Findings after 7 hours at 175 C.

Additive according to invention No change. Commercial gear oil additive on Over 2% insoluble parts.

phosphorus sulfur base. Coiirlimercial zinc dialkyl dithiophos- Spontaneous decomposition.

p ate.

Lubricating oil mixture I Findings after 100 hours at 130 C 5% additive according to invention N change.

in mineral oil SAE 30.

% commercial extreme pressure Oil-insoluble sediments.

additive in mineral oil SAE 30.

2% zinc dialkyl dithiophosphate in Decomposition products of the mineral oil SAE 30. zinc dialkyl dithiophosphate.

Example 8 The good stability of the lubricants according to the invention in prolonged contact with hot metal parts is shown by the following comparative tests, wherein the lubricating oil that contains the additive is pumped in recycle over a tin plate strip heated to 275 C. for 5 hours (BASF Strip Test).

1. A lubricating oil composition comprising a major proportion of a mineral lubricating oil to which has bee added in the range of from 1 to 20 wt. percent of a poly functional additive obtained by first treating polybuten of molecular weight in the range of 500 to 2000 with P 5 to prepare phosphosulfurized polybutene of phosphoru content in the range of 2 to 8 wt. percent and sulfur con tent in the range of 4 to 16 wt. percent, thereafter reactin, the phosphosulfurized polybutene with from 15 to Wt percent, based on said phosphosulfurized polybutene, of monovalent unsaturated fatty alcohol of from 12 to 22 carbon atoms, and subsequently treating the product 0 the last recited reaction with from 1 to 20 wt. percen (based on said last recited product) of an alkylene polyamine having from 3 to 5 amino groups, said polyfunctional additive imparting to said composition conosior inhibiting, detergent, dispersant, and extreme pressure properties.

2. A lubricating oil composition as defined by claim 1 wherein said reaction with said unsaturated fatty alcohol is conducted at a temperature in the range of from about to 200 C. and wherein said reaction with said polyamine is conducted at a temperature in the range of from about 80 to C.

3. A lubricating oil composition as defined by claim 1 wherein said unsaturated fatty alcohol is oleyl alcohol.

4. A lubricating oil composition as defined by claim 1 wheerin said alkylene polyamine is dipropylene triamine.

5. A lubricating oil composition as defined by claim 1 wherein said alkylene polyamine is tetraethylene pentamine.

6. A lubricating oil composition as defined by claim 1 wherein said polyfunctional additive is present in a concentration in the range of about 3 to 5 wt. percent.

References Cited by the Examiner UNITED STATES PATENTS 2,356,073 8/1944 May 25248..4 2,392,252 l/1946 May 25232.7 2,619,462 11/1952 Beare 25246.7 2,809,934 10/1957 Alford et al 25232.7 2,849,398 8/1958 Moody et al. 25232.7

DANIEL E. WYMAN, Primary Examiner.

L. G. XIARHOS, W. H. CANNON,

Assistant Examiners. 

1. A LUBIRICATING OIL COMPOSITION COMPRISING A MAJOR PROPORTION OF A MINERAL LUBIRICATING OIL TO WHICH HAS BEEN ADDED IN THE RANGE OF FROM 1 TO 20 WT. PERCENT OF A POLYFUNCTIONAL ADDITIVE OBTAINED BY FIRST TREATING POLYBUTENE OF MOLECULAR WEIGHT IN THE RANGE OF 500 TO 2000 WITH P2S5 TO PREPARE PHOSPHOSULFURIZED POLYBUTENE OF PHOSPHORUS CONTENT IN THE RANGE OF 2 TO 8 WT. PERCENT AND SULFUR CONTENT IN THE RANGE OF 4 TO 16 WT. PERCENT, THEREAFTER REACTING THE PHOSPHOSULFURIZED POLYBUTENE WITH FROM 15 TO 50 WT. PERCENT, BASED ON SAID PHOSPHOSULFURIZED POLYBUTENE, OF A MONOVALENT UNSATURATED FATTY ALCOHOL OF FROM 12 TO 22 CARBON ATOMS, AND SUBSEQUENTLY TREATING THE PRODUCT OF THE LAST RECITED REACTION WITH FROM 1 TO 20 WT. PERCENT (BASED ON SAID LAST RECITED PRODUCT) OF AN ALKYLENE POLYAMINE HAVING FROM 3 TO 5 AMINO GROUPS, SAID POLYFUNCTIONAL ADDITIVE IMPARTING TO SAID COMPOSITION CORROSION INHIBITING, DETERGENT, DISPERSANT, AND EXTREME PRESSURE PROPERTIES. 